—Peter where did you guys go for the summer vacation?—We busy with our work for months

问题补充：

—Peter, where did you guys go for the summer vacation?

—We busy with our work for months, so we went to the beach to relax ourselves.

A. had been

B. have been

C. were

D. will be

答案：

(答案→)A. had been

B. have been

C. were

D. will be

解析：考查时态：句意：--皮特，你们暑假去了哪里？--我们忙了几个月工作，所以自己去海边度假放松了。根据句意可知，“很忙”在“去海边放松”之前，而“去海边放松”用的是一般过去时went，所以“很忙”应用过去完成时had been。选A。